Rotary oven assembly



5 Sept. 16, 1952 c. K. IDORSEY ROTARY ovzu ASSEMBLY Filed July 26, 1950 2 Sl-[EETS-SI-iEET 2 FIG.3.'

INVENTOR, CARL K. DORSEY, 5v 7 A M TTORNEYS.

' Patented Sept. 16, .1952

STATE-S PATENT Q-FFICE 2,610,592 V ;RQT&RY.;0VEN .ASSEWELY I'Carl'K. Dorsey, Vtebster Groves; Mo.

:AnplicationiJuly: 26, 1950, Serial No. 176,040 107-59) This ;-invention ,7 relates to .;improvements mtary even; assemblies, andlmore particulalzly to an, improved mechanical dri-vel assembly for; re-

tatable shelf structures of.;stabili zed-type. It;is

zprevalentiin-the tradeto ref-er to anorganization of, rotary shelves forgthe; supportofproducts such as-b k ?eQ dse aslalmt rycoven 0 r o in .oven; altlaogzgh-z suchistructur e does not=-of;itself, include-the even chamber. e v

Certaineexistingequipment of.;the ;aforesaid vtypeinvolvesasshelf whee 1,.an eccentric stabilizer ri n g, and; a so-calledcoastenshaft oragu-ide' shaft, upon? or;byqwhich-the;stabi1izer;ring is positioned ;or supported. rHBIfGlSOf-QIB considerable igdifilcul lesvand highaservicecosts.ghave' been;incurr.ed bv reason lof -the diflicul-ty 70f :maintainingtdependablelubricationt and ;hence idependablyejree operation -,0f. 11he coaster-shaft. 'su'chwa vshaft will; frequentl seizeorj; freezeiiin its bearings; defeating itsi'i-ntended :purpose,=:and res'ultin in an, Overload of drivezmotorrand transmission. Very lfrequently, -=such ::shaft :seizure. results in-,:scoring;;or grooving to. the point1pofz :destruction of the-noastercshaf-t, or.;a;head or Wheel ib lfin;: nsagingutheastabilizersring. The pres-'- ent inveI- tion accordingly has ;as :a :major objec .tive,=-.the;avoidance of such sources-of destruction of parts; and: the :realization: of a smoothly operating s tabi-lizedrshel-f even -;assembly, "for .long periods: ofqti-me and under .the prevalent adverse temperature conditions -;encountered in oven operation. ITheeexample selected-to be currently described ,was designed ;primarily .for 'ibakery ovens, but definitely without any express5 or"im plied limitation to any i such specific tfield of :application. I

.The present inventions-may perhaps: best be summarized by :reference (to the embodiment seilecitedjfor. present;di'sclosure,-as including, in preferredhform, ,a main shelf :wheel shaft provi'dedlwith spaced wheel elements or spiders,- between and tQLtheLlatterheing pivoted-a plurality 'ofeeyeulylangulaifly spacedishelves or trays for suppbrt ngthesproducts undergoing baking.- :fIhe

individualshelves :are j-connected through cranks orjil, ks, to .a icommon ,stabilizer element, this being linthe present case anannulus or'ring, to

which,,;throughecrankslorthe .like, the individual shelves are pivotally connected. K'The stabilizer rin ...is eccentrically located with respect to r the axis of theshelf wheel. The stabilizer ring is guidedand supportedgat leastin part,-.b-y-:a stabilizeLShaftQmoreparticularly ahead or separate fridtitlnldr-ive wheel thereon operating. in .direc.t engagement with the ring. A prime mover such .asuan electricWmotor is connected througheaere- Qducingi transmission agency-to the 'wheel shaft and, :by: preference .through :the latter elements ,are provided for e-power transmission :to the coaster or.- guide shaft forthe ring insuchzmanner .that "the latter is: positively driven intim'ed relation to .the shelfwheel, although the-.:cjonnection between the-stabilizershaft and stabilizer .is spreferablyzof some releasabletype suchgas a friction drive.

. In furtherance of: minimizing the jefiect "of? high temperatures on 1 lubrication and ;on the power transmitting elements of the -system, auxinsulated wall :isprovided .asga part of the' oven structure, and v-the main "wheel shaft pas wfell as the stabilizershaft: are journalledin antifric'tion hearings wholly externally of :the ovenran'd externally of. the insulated wall; it being preferred to provide-a separate mechanicalicompartmentviat one end or side of the oven structurerso-rasrto support and house all ofthe. I principal; journals for the-"shafts as welljas the motor and 'all iele- -1 nents of the power-transmission *o'p'erating both the main \shaft-andrstabilizersor coaster shaft;

A-further rimportantrobjectrand advantage of the present improvements :is' realized Till;- the provision of3a istabilizer shaft; together with means for :positively rotatingsaid shaft'fin Idefi nitely timed; relation to :the stabilizer; and. hence; Lto' the main 5 shelf. wheel, thus obuiating manyi ofithe heretofore prevailing "destructive effects on :the

stabilizer'ring-f nd stabilizer shaft.

:Yet; another object ofxa'smajor l'practical importance, :is :the provision :of antifriction hearings,-. for example those of? roller type, and an advantageous location ofi such bearings, so as to obviatethe diihculties heretofore ex erience in coaster "shaft maintenanceand'-operation.

A still furthertaobject of the -='pre'se'n't impro lements is realized ina novelphysical spaeerela tion of the "power transmissionequipment to the oven and thethermal protection of the transmission as by an insulated vbarrier- Pfrom ithe oveniproper.

The foregoing and *numerous o'th'er 'objects will more clearly appear from the rfollowing de'tailed description of a currentlyigpreferred embodiment of the improvements, gparticularlywhen "considered in connection with the accompanying drawings,-i n'-Which:

Fig. -.1"is a vertical-sectional ielevation sshowing :the "rotatable 's-helf ia-ssembly :and'iporti'ons of the oven'structure, fromw-iwhiehwthe :front Wall or otherrclosure is-reinoved to reveal' the :equipment internally of the oven;

Fig. 2 is a sectional view in a vertical plane, showing certain of the drive or power transmission elements, Fig. 2 being located by line 2-2 of Fig. 1;

Fig. 3 is an end elevational view of the shelf wheel or carrier, as viewed along line 3--3 of Fig. 1, and revealing the structural and functional relation of a stabilizer element to the shelf Wheel;

Fig. 4 is a view similar to Fig. 3, but showing the shelves and the stabilizer ring somewhat angularly displaced, relative to the showing of Fig. 3, and

Fig. 5 is an enlarged elevational view, partly in section, of a combined shelf hanger and crank arm, together with certain parts immediately connected thereto, this figure being located by line 5-5 of Fig. 3.

Referring now by characters of reference to the drawings, the oven structure proper, which defines and encloses the baking chamber, includes a top wall ID, a bottom wall II, a side wall I2 and an opposite side wall generally indicated at I3. Each side wall is comprised of a pair of relatively heavy vertical closure elements such as I 4 which may be of metal, the pair thereof in each wall being spaced in parallel relation. Between adjacent elements I4 is a body of a mineral insulating material indicated at I I5, which construction of course minimizes oven heating energy and serves materially to reduce the temperature ranges normally prevailing just outside the oven proper, and in a laterally adjacent mechanical compartment I6. This latter may be left open in part, subjected to forced air circulation if desired, and where indicated may be further enclosed by an outermost wall element I 1. Heating means for the oven chamber, the latter generally indicated at 20, are omitted since, per se, constituting no part of the present improvements.

Supported within the oven chamber is a main wheel shaft 2| which is of substantial diameter, and spaced axially of which are a pair of shelf wheel elements or spiders 22 at the left (Fig. 1) and 23 at the opposite end. Pivotally supported between the spiders or wheel elements 22-23 are a plurality of evenly angularly spaced shelves or trays 24. Rigidly affixed to the opposite ends of each shelf 24 are a pair of shelf hangers 25 certain of which, being those on the right hand side (Fig. 1) of the assembly constitute portions of the crank or link elements best shown in detail in Fig. 5; however, in either case the shelf hanger proper is attached to a horizontal stub shaft portion 26 as through a stud 21, the elements 26 being journalled in the periphery of the adjacent wheel or spider such as 22' or 23, an aluminum-bronze bushing 30 being located in the portion shown, in the periphery of each spider at each'of the shelf hanger locations.

Fixedly attached to those of the elements 26 engaging the spider-wheel 23, is a link or crank arm 3 I, each of the elements 3| engaging a short journalled stub shaft portion 32 freely rotatable within an anti-friction bearing shown and preferred as a roller assembly 33. These journal assemblies are evenly disposed about the inner periphery of the stabilizer rotor or ring 34, as will appear.

The stabilizer element such as ring 34, surrounds with a wide spacing, the main drive shaft 2| which serves the shelf carrier or wheel, and is entirely free of any direct connection with the shaft and in fact may be described as fioatingly .4 positioned in the chamber 20 although constrained to a substantially fixed position by reason of the connection thereto of the several links 3|. The ring 34 is, however, guided, positioned and to some extent supported by a milled or knurled friction driving head 35, also in the chamber 20, and carried at the inner end portion of a stabilizer shaft, sometimes designated in the trade as a coaster shaft 36.

It will be understood that the assembly of shelves with the spiders or wheels 2223, is angularly fixed to the main shaft 2I. Such attachment means may include a flanged hub structure including wheel plates 31, shaft-engaging flanges 4U, suitably attached to shaft 2i, and studs or equivalent fastening means 4 I.

It may be noted that the practice of providing a shelf wheel as or in a revolving oven assembly, together with a stabilizer element, is, in a broad sense, well known in the art; however, as will have appeared, the present assembly includes numerous features of improvement which conduce to longer low-cost operational life, added stability of the shelving or trays, and a much reduced service expense.

Proceeding now to describe the mechanical drive of the shelf structure and stabilizer ring, it is a matter of convenience and compactness of assembly, as well as to provide thermal protection against heat of the oven, that the power unit and transmission elements are located in the mechanical compartment I6. These elements include a prime mover, exemplified as an electric motor to which is operatively connected, as through a single or multiple V-belt 46, a speed reducer unit 41, the takeoff shaft of which carries a drive pinion enmeshing with a relatively large ring gear 5| attached through a hub 52 to a continuation 53 of the main shelf wheel shaft 2|. Anti-friction bearings, fully enclosed, preferably of roller type and serving the main shaft are indicated at 54 carried by wall ll, 55 carried by one of the wall elements I4, and 56 at the opposite end or side of the oven. Thus it will appear that when motor 45 is energized, pinion 50 will be driven at a considerably reduced rate, there being a further operative speed reduction between elements 50 and 5|, thus driving the shelf wheel at a rate of only a few R. P. M. If desired the unit 41 may be of variable-ratio type, and if desired, motor 45 may be of variable speed type. Further and now obviously, other changes may be made in the ratio of drive, to attain any particularly desired operative speed of the shelf assembly.

It is a valuable and very important feature of the present improvements to preclude virtually any possibilityof a continued operation of the stabilizer ring 34 when the shaft and drive head 35, 36 are precluded from operation, as by seizure of shaft 36. The shaft 36 is journalled, as will appear, entirely outside of the hot oven chamber 20. In the present example, shaft 36 is short, and is rotatably supported in a pair of antifriction, preferably roller type bearings, these assemblies being indicated at 60, carried by the outermost of theadjacent paired wall elements I4, and GI carried by the support or wall I'I. All of such roller type bearings in the present assembly may be packed with a special heat-resisting lubricant, and so will operate for long periods without routine lubrication attention.

Reference will now be made to a preferred arrangement for a positively powered operation of the shaft 36 and the head or wheel 35 thereon, so

wheel structure serving operatively to connect said power means to the stabilizing member.

7. An oven comprising a plurality of shelves, means to which the shelves are pivotally connected for moving same in an orbital path, means for preventing unwanted displacement of the shelves during the orbital movement thereof, said means comprising a stabilizer ring, a ivotal connection from such ring to each of the shelves, a rotary guide element engaging a marginal portion of the ring and power-driving means distinct from the ring, for rotating said guide element.

8. In a revolving oven structure, a shelf wheel, a plurality of shelves thereon, a shaft for the shelf wheel, a power unit, means for driving the shaft in predetermined timed relation from the power unit, a stabilizer ring connected to the shelves and acting to keep same horizontal during rotation of the shelf wheel, a shaft directly operatively connected to the stabilizer ring, and means energized from the power unit for driving the last said shaft in timed relation to the wheel and to the ring,

9. In a rotatable oven of a stabilized-shelf type,

a shelf wheel, a plurality of shelves carried by the Wheel, a wheel shaft, a gear on the wheel shaft, a power unit, means for driving said gear from the power unit, a stabilizer ring rotatable with the wheel and connected to and acting to keep the shelves horizontal throughout rotation of the shelf wheel, a shaft directly operatively connected to the stabilizer ring, and means for drivin the last said shaft from said gear, in definitely timed relation, and in a direction of rotation opposite to that of the wheel and ring.

10. In a rotary oven of a stabilized-shelf type, a rotatable shelf supporting structure including a shaft therefor, means acting responsively to rotation of said structure to stabilize the shelves,

said means including a stabilizing rotor eccentrically related to the shelf supporting structure, a coaster shaft directly operatively connected to said rotor and arranged for positioning same, and means distinct from the rotor for driving the coaster shaft in definitely timed relation to the shaft of the rotatable shelf structure.

11; In an oven, two rotary wheels or spiders rotatable about a common axis and spaced therealong, a plurality of shelves supported between said wheels, a pair of hangers for each shelf, one

hanger being located at each end of each shelf, said hangers being pivotally connected to the shelf wheels and attached to the shelves, bearings at the ends of said shelves adjacent said wheels,

said bearings being of sleeve type, a stabilizer ring eccentric to the axis of said shelf wheels, and bearings on said ring, the last said bearings being of roller type, and a link connection between the stabilizer ring and each of said shelves, the eccentricity of said stabilizer ring being such that said bearings and links coact to maintain the shelves horizontal in all positions of the wheels, and a rotary powered element operatively engaged by the stabilizer ring, and through which a turning moment is directly applied to said ring during operation of the wheels.

12. In a rotary oven assembly, means enclosing an oven chamber, said enclosing means including a thermally insulated vertical wall, a revolving shelf wheel in the oven chamber, a wheel shaft extending through said insulated wall, a power unit located externally of the insulatedwall, and operatively connected to said wheel shaft, a shelfstabilizing ring in the oven chamber coacting with the shelf Wheel, a ring-positioning shaft located partly in the oven chamber and artly outwardly of the insulated wall, journals for each of said shafts, said journals being located laterally and exteriorly of the insulated wall, and power transmission means located outside of the oven and insulated wall, and being actuated by the power unit and operatively connected both to the shelf wheel shaft and to the ring positioning shaft.

13. In a revolving oven assembly, a plurality of shelves, a wheel structure by which the shelves are carried, a stabilizer ring located externally of the wheel, a link element pivotally connecting the stabilizer ring and each of the individual shelves, a main supporting shaft for the shelf wheel, a ring-guiding shaft engaging the periphery of the stabilizer ring, and located to support and guide the ring, means for rotatably actuating said main wheel shaft, and power transmission means interconnecting the first and second said shafts, whereby to drive the second said shaft in predetermined timed relation to, but in a direction opposite to that of the first shaft.

14. In a revolving oven assembly, a revolving shelf assembly within the oven chamber and including a pair of spaced spiders, a main shaft by which said spiders are rotatably carried, a plurality of shelves for supporting articles to be exposed to baking temperature, said shelves being provided with hangers, one at each end of each shelf, the shelf hangers being journalled in the spiders, a plurality of cranks, one for each shelf, carried by the shelves and one of the spiders, a stabilizer ring free of the said main shaft, but surrounding same in substantially spaced relation, the stabilizer ring being located in the oven chamber, and pivotally connected to the several cranks, and therethrough to the shelves, the ring being located eccentrically of the main shaft and the spiders, a coaster shaft serving as a guide for the stabilizer ring, the coaster shaft provided with roller type bearings, a metal friction Wheel carried by an inner end portion of the coaster shaft, and frictionally engaging the outer periphery of the stabilizer ring, a power unit and transmission means including a ring gear carried by said main shaft, a motor, a speed reduction unit, a pinion engaging the ring gear and driven from said reduction gear unit, a gear driven from the ring gear and a power connection from the ring-driven gear to the coaster shaft, and arranged for rotation of the coaster shaft in timed relation to, but in a direction 0pposite the direction of rotation of the main shaft.

15. In a revolving oven assembly, an enclosure defining an oven chamber, the enclosure structure including a thermally insulated vertical side Wall, and anauxiliary closure spaced from said insulated wall to form therewith a mechanical compartment, a revolving shelf assembly within the oven chamber and including a pair of spaced spiders, a main shaft by which said spiders are rotatably carried, a plurality of shelves for supporting articles to be exposed to baking temperature, said shelves being provided with hangers, one at each end of each shelf, the shelf hangers being journalled in the spiders, a plurality of cranks, one for each shelf, carried by the shelves and one of the spiders, a stabilizer-ring free of the said main shaft, but surrounding same in substantially spaced relation, the stabilizer ring being located in the oven chamber, and pivotally connected to the several cranks, and there-' coaster shaft serving as a guide for the stabilizer ring, the coaster shaft bridging the insulated wall and the auxiliary closure and provided with roller type bearings located entirely outside of the oven chamber, and a pair of such bearings being carried respectively by the insulated wall and the I cal compartment.

10 shaft in timed relation to, but in a direction opposite the direction of rotation of the main shaft, the said motor, reduction gear unit, and the recited transmission elements associated with the respective shafts, being located in said mechani- CARL K. DORSEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,002,655 Bolling May 28, 1935 2,201,231 Haupt 1- May 21, 1940 

